Abstract # 2234 Event # 6:

Scheduled for Thursday, June 21, 2007 10:30 AM-10:45 AM: Session 1 (North Main Hall C/D) Oral Presentation

Seasonal Influences on Visual Social Monitoring in Free Ranging Lemur catta at Berenty Reserve, Madagascar

L. Lane and K. A. Bard
Psychology Department - King Henry Building, University of Portsmouth, King Henry I Street, Portsmouth, Hampshire PO1 2DY, United Kingdom
     Studies of visual monitoring of conspecifics have focused on avoidance of competition or aggression within groups, whereas fewer data address the role of affiliation in shaping patterns of visual attention. Two additional aspects of visual attention, stability across time, and relation with group social dynamics, are little researched. This study assessed the affiliative basis of social monitoring in Lemur catta across two behaviorally distinct seasons. Social monitoring was observed in a troop of 16 lemurs across approximately 4 months, during birth and mating seasons. Observations of proximity, affiliation and aggression were used to analyze how monitoring varied as a function of the strength and quality of dyadic relationships. Silk’s Sociality Index was computed and dyads classified as friends or non friends. Affiliation strength was positively correlated with social monitoring for all dyad types during birthing season [N=105, r=0.48, p<0.001], whereas in mating season the correlation was significant for females [N=28, r=0.45, p<0.05]. Aggression was unrelated to social monitoring during birthing season, but positively correlated with monitoring during mating season for males [N=10, r=0.79, p<0.05]. We conclude that there is stability in the pattern of visual monitoring for female lemurs, especially in monitoring friends, but not so for males. Visual monitoring has an affiliative basis in females and males, but male social monitoring also reflects changes in male-male competition during mating season.